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United States Patent | 5,560,898 |
Uchida ,   et al. | October 1, 1996 |
Carbon nanotubes are isolated from a mixture containing the carbon nanotubes and graphite particles by a process including the steps of: finely pulverizing the mixture; dispersing the pulverized product in a liquid medium; centrifuging the resulting dispersion to obtain a supernatant containing carbon nanotubes and graphite particles having a particle size of 0.3 .mu.m or less; separating the supernatant into a solid phase and a liquid phase; and calcining the solid phase in an oxygen-containing atmosphere at a temperature sufficient to burn the graphite particles and to leave the nanotubes.
Inventors: | Uchida; Kunio (Tsukuba, JP); Yumura; Motoo (Tsukuba, JP); Ohshima; Satoshi (Abiko, JP); Kuriki; Yasunori (Tsukuba, JP); Yase; Kiyoshi (Tsukuba, JP); Ikazaki; Fumikazu (Tsukuba, JP) |
Assignee: | Director-General of Agency of Industrial Science and Technology (JP) |
Appl. No.: | 283508 |
Filed: | August 1, 1994 |
Aug 04, 1993[JP] | 5-212270 |
Current U.S. Class: | 423/461; 423/445B; 423/447.2; 977/DIG.1 |
Intern'l Class: | D01F 009/12; C01B 031/02 |
Field of Search: | 423/445 B,DIG. 39,DIG. 40,447.2,461 |
4254823 | Mar., 1981 | Cederqvist | 162/55. |
5346683 | Sep., 1994 | Green et al. | 423/445. |
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